1. Field of the Invention
The present invention generally relates to integrated circuits and more specifically to an insulator that simultaneously dissipates heat from high power devices using a high K insulator material and accommodates the low electrical permitivity/resistance needs of low power logic devices using a low K insulator material.
2. Description of the Related Art
With the advent of high performance/low power integrated circuit devices, low K dielectrics are commonly used to insulate the devices from adjacent substrates. Low K dielectrics offer reduced electrical permitivity and reduced thermal resistance when compared to high K dielectrics. While such electrical characteristics are very beneficial to low-power devices (such as critical paths, logic chains and other core logic devices), the low K dielectrics do not offer the high thermal conductivity which is required by high-power devices, such as electrostatic discharge (ESD) devices, clock buffers, and input/output (I/O) drivers.
Therefore, the integrated circuit designer must balance the electrical needs of the low-power devices against the thermal needs of the high power devices. This compromise reduces the performance of the low-powered devices and constrains the amount of heat which can be generated by the high-power devices. The invention described below eliminates this tradeoff and allows the integrated circuit designer to improve the performance of the low-powered devices and, at the same time, allows the high-powered devices to generate additional heat. Thus the invention overcomes self heating of ESD structures, interconnects and circuits.